* add a wasi-test to show a dir_fd always gets ERRNO_BADF on appropriate fd_ operations. This is a conformance test for the current behavior of preview 1 in wasi-common. It is debatable whether this is the right errno, I think for most of these ERRNO_ISDIR would be more descriptive, but this is the behavior we have. * Add comments to all the fd op failures explaining closest linux/posix behavior
This is the wasi-tests crate, which contains source code for the system-level WASI tests.
Building these tests requires that the wasm32-wasi target be installed.